I would recommend a discharge line pressure drop of 2-5 psi/100ft at normal condensing temperature, as it should not greatly effect the operating efficiency of your system. For the liquid line between the condenser and receiver (or high-side float), I would use a velocity of 75 fpm for small pipe to 150 fpm for larger pipe. An average of 100 fpm works well for sewer-type flow (assuming your condenser is above your chiller). The value can be adjusted based on pipe geometry (NPS, elevation change, distance) and whether or not an external gas equalizing line is used.